Photogravure plate printing press



April 6, 1937.

w. MAILANDER 2,076,203 PHOTOGRAVURE PLATE PRINTING PRESS Filed May 9, 1935 3 Sheets-Sheet l TM/Me for:

April 6,1931 w. MAILANDER 2,076,203-

PHOTOGRAVURE PLATE PRINTING PRESS Filed May 9, 1935 s Sheets-Sheet '5 Patented Apr. 6, 1937 PATENT OFFICE PHOTOGRAVURE PLATE PRINTING PRESS Willy Mailander, Stuttgart-Bad Cannstatt, Germany Application May 9, 1935, Serial No. 20,696 In Germany December 21, 1934 16 Claims.

The present invention relates to a plate photogravure printing machine wherein the flow of the quantity of ink to the surface of the plate can be regulated.

The flow of the quantity of ink generally is regulated in such a manner that between the surface of the plate and the inking roller an accumulation of ink or color is maintained as is necessary in the photogravure printing process,

in order that the shallowest and the deepest etched recesses may become completely filled with ink or color.

With photogravure printing machines as for example with copper cylinder machines, where 15 the inking roller is not guided, this slight accumulation of ink is of no importance; however,

in the case of plate machines, the accumulation of ink left when the inking roller is lifted off the surface of the plate or when leaving this surface,

has a very disadvantageous effect, especially as a consequence of the high rotary speed of the inking roller and inasmuch as the machine is sprinkled with ink when the accumulation of ink gets through between the inking roller and the 25 surface of the plate cylinder. In order to avoid this sprinkling, this accumulation of ink must be removed before the inking roller leaves the surface of the plate cylinder.

This is effected according to the present inven- 30 tion by the fact that towards the end of the inking or color applying position the feed of ink to the accumulation is cut off at just the precisely correct moment prior to complete inking of the plate in order that the thereby isolated ink ac- 35 cumulation will be used up by the required further inking of the plate. By these means the presence of any ink which would otherwise be thrown off, when the inking roller leaves the plate-cylinder, is effectively prevented.

According to the present invention the quantity of ink supplied to the inking mechanism isregulated both as to time and quantity by such control of the inking roller or by the provision of-means which regulate the flow of ink to the 45 accumulation or bead. By mechanically controlling this means or the inking roller the required proper moment for cutting off the ink supply can be accurately adjusted and maintained sothat the bead of ink is used up at the correct 50 moment. Instead of controlling the means to regulate the ink supply or feed, it is also possible to control the inking roller for example by imparting movement to the inking roller towards the regulating means or by varying the circum- 5 ferential speed of rotation of the inking roller.

The ink supply regulating device and the manner of its control may be of any suitable kind. This ink supply device may for example comprise a wiper roller 'or a scraper-knife which is actuated by means of a cam and is adjustable during working.

Further means are provided on the one hand to regulate the lift of the device for the regulation of the ink supply, i. e. the thickness of the quantity of the flow of ink, and on the other hand to secure a minimum flow of ink at each movement of the said device for the regulation of the ink supply, i. e. to prevent the said device, especially if same consists of a scraper knife, from touching the inking roller and thereby damaging the latter. Regulation of the quantity of ink or color fed to the inking roller is necessary in order to control the size of the ink accumulation, which itself depends on the lesser or greater consistency of the ink or color. This regulation is effected by varying the ratio of transformation of the driving rods actuating the device which regulates the ink or color supply, the point at which the ratio of transformation of the driving rods is varied being so chosen, that it is possible to see and observe the inking or coloring zone, 1. e. that it is possible to observe the effect of the change on the ink accumulation during the time that the adjustment of the ink or color supply is effected. The point at which the adjustment is made must therefore be situated not on the outside of the machine, but on the inside thereof, and as near as possible to the inking or coloring mechanism. For this purpose a lever which rocks a control cam may be convenientlyv used, the said cam being adapted to rock the lever, by means of which the regulating device is raised during the period of maximum ink supply.

This regulates or controls the ink or color supply as near as possible to the plate inking zone,'because in this case it is not necessary to throttle the ink supply very much before the inking operation is finished, but only to an extent corresponding to the distance of the effective zone of the regulating device from the inking zone, plus that extent necessary to useup the ink accumulation. To achieve satisfactory results, the working zone, the form of the regulating device, and its disposition and mounting are so chosen, that the regulating device does not obstruct a full view-"of the ink accumulation, in order that the inking zone may be fully visible and thus easily controllable.

As regards the device intended for the purpose of preventing the inking roller being damaged by the scraper-knife, an adjustable stop is provided enabling the minimum distance of the scraperknife from the inking roller to be adjusted. The adjusting device and the stop are mounted on levers which carry the inking roller, the said levers being adapted to be rocked up and down in order to. move the inking roller on to or off the plate-cylinder.

By reason of the fact that the limit-stop for the ink-supply regulating device is mounted on the rockable levers supporting the inking roller, the adjustment of the regulating device relatively to the inking roller always remains the same whether the latter is on or off. This is of importance insofar as the inking roller is adapted to be moved on or off the plate-cylinder by hand, in order to permit ink to be fed into the trough and to be thoroughly mixed, without the ink reaching the plate straight away.

In order to obtain a uniform and consequently regulatable supply of ink to the inking zone, the surface of the inking roller is preferably made, instead of the usual so called composition material, of such a material which is not subject to change in its diameter or dimensions and is easily wiped, scraped and cleaned, a roller made of steel or other suitable metal or alloy is the most suitable for such a purpose.

In order that the invention may be clearly understood and readily carried into effect refer-j ence is made to the accompanying drawings .which show diagrammatically and by way of example two constructional forms of inking mechanism in accordance with the present invention and as applied to a photogravure plate printing press.

Figure 1 is a side elevation of inking mechanism according to the present invention as applied to a photogravure plate printing press only so much of the latter being shown as is necessary for the purpose of the present invention.

Figure 2 is a side elevation showing a modified form of inking mechanism also is accordance with the present invention.

Figure 3 shows the inking mechanism and the several shafts thereon as developed in one plane.

Referring to Figures 1 and 2 an inking roller is shown at I and rotates in the usual manner in an ink trough 2. The roller I is rotatably mounted with-its shaft 3 in levers 4. The" inking roller I is driven by means of cog wheels 5 Figure 3 from the shaft of the plate cylinder 6, the latter being mounted on axle 6'. These levers 4 are rockably mounted on a pin or bolt 1 in order to enable the inlnng roller I to be raised into operative position or lowered into inoperative position as well as for the purpose of adjusting its position accurately relatively to the plate-cylinder an adjustable follower.

6. Raising and lowering of the inking roller I is effected by a cam 8, which is mounted rockably on a pin 9 and is provided with an operating handle Ill. The levers 4 carrying the inking roller I rest by gravity on the cam 8, manually operable adjusting screw II being provided between the levers 4 and the cam 8 and acting as By adjusting the screw II the gap between the inking roller I and the cylinder 6 can be varied. The inking roller I is put into or out of action by rocking the cam 8 by means of the handle I0.

In order to regulate and control the supply of ink to the inking zone I2 according to the present invention a means is provided for this purpose, which means comprise according to Figure 1 a scraper-knife I3 and according to and the larger the size of the ink accumulation I becomes which forms between 'the plate cylinder 6 and the inking roller I.

The scraper-knife I3 is arranged in such manner that it does not obscure the visibility of the inking zone I2, and is for example downwardly inclinded in an outward direction, in order that the excess ink may flow off and be guided into the ink trough 2 by means of a gutter I5 extending into the said trough 2. The gutter I5, together with the scraper-knife I3 and the inking roller I form a cover forthe ink trough thus preventing or tending to prevent evaporation of the ink in the said trough 2.

According to the present invention the scraper-knife I3 and consequently also the supply of ink to the inking zone I2 are mechanically controlled in such manner, that the accu mulation of ink formed between the inking roller I and the plate cylinder 6 is completely used up when the whole of the etched plate has been inked. Forothis purpose the free passage or duct left for the passage of the ink between the inking roller I and the scraper-knife I3 is automatically varied, that is to say, the scraperknife I3 can be adjusted towards the end of the inking operation, relatively to the inking roller I so that no ink or only very little can pass through. This displacement or adjustment of the scraper-knife I3 or the control thereof is effected by means of a cam 22, (Figures 1 and 2) which is conveniently disposed at the bottom of the press but which may be mounted on any of the rotating shafts present which make one revolution during each impression. The cam 22 controls and actuates a bell crank lever 23 carthe cam 22. The lever 23 by means of a link or rod 25 rocks a lever 26 which in its turn rocks a camv 21, which is mounted on the fulcrum of the supporting levers 4. The cam 21 acts through the roller or follower 28 on the supporting lever I6 carrying .the scraper-knife I3. When the roller 24 on the lever 23 mounts the raised portion of the cam 22, the cam 21 is rocked, and consequently also the supporting lever I6 carrying the scraper-knife I3, thus allowing the normal quantity or a. greater quantity than the normal quantity of ink to pass through the duct between the scraper-knife and the inking roller. When later the roller 24 runs down from the raised portion of the cam 22 to the low portion of the said cam 22 the scraperknife I3 is again lowered towards the circumference of the inking roller I, and the supply of ink to the inking zone is restricted, which occurs, according to the present invention at the moment, when the inking nearly reaches the end of the plate to be inked, and this restriction or cutting off of the ink supply occurs at the proper 'is arranged at or near the fulcrum of the supporting lever 4 of the inking roller I and near to the roller-follower 28 'with the result that when the inking roller i is rocked to bring it into or out of action, the distance of the roller 28 from the cam 21 is not at all or only very slightly altered.

In order to cut off the ink supply early or late, the cam 22 is adapted to be adjusted by moving the cam round to the required extent in order that the active part of its circumference may become operative on the roller 24 sooner or later as required.

The cam 22 is preferably of such a design, that the scraper-knife i3 is moved into its throttling position as quickly as possible. The result is that the accumulation of ink is used up rapidly as soon as the ink supply is cut off. This enables the extension that is the dead end of the-plate at the end of the etched part, to be reduced to a minimum.

The cam 21 controlling the scraper-knife l3 does not act directly on the lever l6 carrying the scraper-knife, but on the roller 28 mounted on a. third arm 29 of the supporting lever IS. The roller 28 however does not lie directly on the cam 21 but is allowed a certain amount of play in order to enable a stop 20 to lie against a stopscrew 2|, when the scraper-knife I3 is in a position to cut off the ink supply.

The lift of the scraper-knife I3 from the inking roller can also be varied by altering the ratio of transformation of the driving rods of the transmitting links or rods of the control-device. The point at which this change is effected is preferably so chosen, that during any alteration the inking zone l2 and the ink being supplied thereto can be easily seen thus providing for the change to be effected correctly and at the proper time. Consequently the alteration or adjustment is preferably effected on the lever 26 controlling the cam 21. In order to achieve this a bar or link is connected with the lever 26 in such manner, that its operative part is adapted to be advanced more or less towards the fulcrum l of the cam 21!. This is attained, by adapting the connecting pin 30 so that it can be radially 4 displaced within a slot 3! provided in the lever 26, such displacement being effected by means of a manually adjustable screw 32 thus displacing the connecting pin 30 towards the fulcrum i of the cam 21.

The cam 21 is preferably mounted as near as possible to the fulcrum pin I of the supporting lever 4 carrying the inking roller 1, and still more preferably on the pin I itself, in order that the mutual positions of the roller-follower 28 and the cam 2! maymemain constant even when the inking roller l is moved into or out of action.

The material used for the inking roller I is preferably such that it does not change as regards its diameter and that it can be easily scraped and cleaned. A metallic material such as steel is particularly suitable for this purpose.

What I' claim is:-

1. A process of inking a photogravure plate from a fountain roller comprising maintaining an accumulation of ink at the line of cooperation between the fountain roller and the plate, applying ink progressively over the plate from said accumulation, and stopping the feed of ink to the accumulation at such an instant during the application of ink'to the plate that the accumulation will be used up in completing the inking of the plate.

2; A process of inking a photogravure plate from a fountain roller comprising maintaining an accumulation of ink at the line of cooperation between the fountain roller and the plate, moving the printing surface of the plate progressively into contact with the ink accumulation to apply 'ink to said surface, and stopping the feed of the ink to the accumulation when a predetermined area of said surface has been inked, the remaining area being inked by using up the unrenewed accumulation.

3. In a plate-photogravure printing press, a printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, means for moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for interrupting renewal of said ink accumulation, and means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption.

4. In a plate-photogravure printing press, a printing plate, a fountain roller adapted to maintain an accumulation of ink along its line of cooperation with said plate, means for progressively moving the printing surface of the plate through said accumulation, means for controlling the layer of ink fed on said roller towards the accumulation, and means for timing the operation of the controlling means to cut off the feed of said layer at a predetermined instant before the entire surface of the plate has/progressed through said line whereby the rest of said surface is inked by using up the accumulation.

5. In a plate-photogravure printing press, a

printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, means for moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for abruptly interrupting renewal of said ink accumulation, and means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption.

6. In a plate-photogravure printing press, a printing plate, a fountain roller adapted to hold and feed an accumulationof ink along its line of cooperation with the plate, means for varying the magnitude of the ink accumulatiommeans for moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for interrupting renewal of said ink accumulation, and means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption.

7. In a plate-photogravure printing press, a printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, meansfor moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for interrupting renewal of said ink accumulation, means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation v said surface, a wiper cooperating with the surface of the fountain roller to control the feed of ink to the accumulation, means for moving the wiper to interrupt said feed, and means for so timing the wiper moving means as to synchronize passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption.

9. In a. plate-photogravure printing press, a printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, means for moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for interrupting renewal of said ink accumulation, means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption, and means for moving the fountain roller towards and away from the printing plate.

10. In a plate-photogravure printing press, a

printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, means for moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for interrupting renewal of said ink accumulation, means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption, an ink reservoir cooperating with the fountain roller, and a. drip device associated with the interrupting means for returning ink to the reservoir.

11. In a plate-photogravure printing press, a printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, means for mov- 40 ing the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, a wiper cooperating with the surface of the fountain roller to control the feed of ink to the accumulation, means for moving the wiper to interrupt said feed, means for so timing the wiper moving means as to synchronize passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said 50 interruption, and an adjustable stop for determining the limit of approach of the wiper to the surface of the fountain roller.

12. In a plate-photogravure printing press, a printing plate, a fountain roller with a metallic surface adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, means for moving the printing surface of the plate in contact with said ink accumulation to apply ink progressively over said surface, means for interrupting renewal of said ink accumulation, and means for synchronizing passage of the end of the printing surface through said line with exhaustion of the ink accumulation consequent upon said interruption.

13. A plate-photogravure printing press comprising a printing cylinder, a fountain roller capable of holding and feeding an accumulation of ink at its line of cooperation with said cylinder, a scraper knife cooperating with the fountain roller, manually operable means for adjusting the scraper knife relatively to the fountain roller, mechanically operable means for causing the knife to interrupt the feed of said ink accumulation by the fountain roller, and means for timing such interruption to occur at a predetermined instant before completion of the inking of said cylinder.

14. In a plate-photogravure printing press, a printing plate, a fountain roller adapted to hold and feed an accumulation of ink along its line of cooperation with the plate, meansfor automatically controlling the quantity of ink supplied to the ink supplying zone of the printing plate, lever means for carrying the inking roller, and a rockable cam arranged adjacent the fulcrum of the lever means for the ink supply.

15. A plate-photogravure printing press according to claim 14, in which the means to regulate the ink supply is mounted on the lever means.

16. A plate-photogravure printing press according to claim 14, in which the means for controlling the quantity of ink includes a plurality of rods or links which are varied manually at such a point close to the inking zone that the effect of the variation made can be observed at the inking zone while such variation is being effected.

WILLY MAILANDER. 

